There have been proposed techniques for creating a database in which the identification codes for identifying metadata items are associated with the readings (i.e., names) of the items in such a manner that the name of a given metadata item may be determined by searching through the database for the identification code of the item in question. One such technique (e.g., proposed in Japanese Patent Laid-open No. 2004-206648) involves getting a user terminal to read a TOC (table of contents) from a CD or a DVD as an identification key that determines the names of metadata items held on the storage medium so that the user is informed of the reading of any given metadata item.